From da1316d146ad857f601dd32b1709935be1b11a8c Mon Sep 17 00:00:00 2001
From: Hayden Spitzley <105455169+hspitzley-czi@users.noreply.github.com>
Date: Fri, 3 May 2024 09:55:10 -0700
Subject: [PATCH] fix: suppress decompression error and treat uncompressed
 token in cache as cache miss (#1058)

---
 oidc_cli/oidc_impl/cache/cache.go      | 16 +++++++++-------
 oidc_cli/oidc_impl/cache/cache_test.go |  2 +-
 2 files changed, 10 insertions(+), 8 deletions(-)

diff --git a/oidc_cli/oidc_impl/cache/cache.go b/oidc_cli/oidc_impl/cache/cache.go
index b973fe1d..8451bb5b 100644
--- a/oidc_cli/oidc_impl/cache/cache.go
+++ b/oidc_cli/oidc_impl/cache/cache.go
@@ -116,10 +116,11 @@ func (c *Cache) readFromStorage(ctx context.Context) (*client.Token, error) {
 	// decode gzip data
 	decompressedStr, err := decompressToken(*cached)
 	if err != nil {
-		return nil, fmt.Errorf("failed to decompress token: %w", err)
+		// if we fail to decompress the token we should treat it as a cache miss instead of returning an error
+		logrus.Debug(fmt.Errorf("failed to decompress token: %w", err).Error())
 	}
 
-	cachedToken, err := client.TokenFromString(&decompressedStr)
+	cachedToken, err := client.TokenFromString(decompressedStr)
 	if err != nil {
 		logrus.WithError(err).Debug("error fetching stored token")
 		err = c.storage.Delete(ctx) // can't read it, so attempt to purge it
@@ -142,18 +143,19 @@ func compressToken(token string) (string, error) {
 	return buf.String(), nil
 }
 
-func decompressToken(token string) (string, error) {
+func decompressToken(token string) (*string, error) {
 	reader := bytes.NewReader([]byte(token))
 	gzreader, err := gzip.NewReader(reader)
 	if err != nil {
-		return "", fmt.Errorf("failed to create gzip reader: %w", err)
+		return nil, fmt.Errorf("failed to create gzip reader: %w", err)
 	}
 	decompressed, err := io.ReadAll(gzreader)
 	if err != nil {
-		return "", fmt.Errorf("failed to read gzip data: %w", err)
+		return nil, fmt.Errorf("failed to read gzip data: %w", err)
 	}
 	if err := gzreader.Close(); err != nil {
-		return "", fmt.Errorf("failed to close gzip: %w", err)
+		return nil, fmt.Errorf("failed to close gzip: %w", err)
 	}
-	return string(decompressed), nil
+	decompressedStr := string(decompressed)
+	return &decompressedStr, nil
 }
diff --git a/oidc_cli/oidc_impl/cache/cache_test.go b/oidc_cli/oidc_impl/cache/cache_test.go
index 5016a500..98e11fdf 100644
--- a/oidc_cli/oidc_impl/cache/cache_test.go
+++ b/oidc_cli/oidc_impl/cache/cache_test.go
@@ -88,7 +88,7 @@ func TestCorruptedCache(t *testing.T) {
 	decompressedToken, err := decompressToken(*cachedToken)
 	r.NoError(err)
 
-	tok, err := client.TokenFromString(&decompressedToken)
+	tok, err := client.TokenFromString(decompressedToken)
 	r.NoError(err)
 	r.NotNil(t)